<?php
$str = 'Acer-laptop-battery/Acer-3UR18650F-3-QC151-battery-17.html';
$reg = '/battery\/(.*)-battery-.*\.html/U';
$s = preg_match_all( $reg, $str, $arr );
echo "<pre>";
print_r($s);
echo "<br>";

print_r( $arr );
echo "</pre>";
?>